Evidence for production of an enterotoxin and cholera toxin cross-reactive factor by Aeromonas hydrophila.

The enterotoxins produced by Aeromonas hydrophila were examined for biological activity by the rabbit ileal loop and suckling mouse assays, as well as by elongation of CHO cells. Antigenic evaluation of the culture filtrates from various isolates of A. hydrophila was performed by enzyme-linked immunosorbent assay with anti-cholera toxin and anti-Aeromonas enterotoxin. Heat stability data demonstrated the presence of a heat-labile cholera toxin cross-reactive factor and a heat stable non-cholera toxin cross-reactive enterotoxin. The biological activities of both enterotoxins were heat labile at 56 degrees C for 20 min.